Oklahoma wheat producers should assess topdress needs

Wheat producers should be making plans to assess their crops’ topdress nitrogen requirements as accurately as possible.
A producer needs to look at how many acres he or she has to topdress and the capacity to cover those acres.
Nitrogen fertilization remains an excellent return on investment.

Donald Stotts, OSU | Dec 22, 2011

Wheat producers should be making plans to assess their crops’ topdress nitrogen requirements as accurately as possible, according to Oklahoma State University’s Division of Agricultural Sciences and Natural Resources.

“Oklahoma is the fourth-largest wheat-producing state in the nation, and every acre is a managerial and monetary investment to the producer who planted it,” said Jeff Edwards, OSU Cooperative Extension small grains specialist. “Most Oklahoma producers should plan to assess their topdress requirements between Jan. 1 and March 1.”

With so much acreage to cover, some producers naturally will start earlier than official management recommendations and some will begin later.

“When we provide recommendations, we give out the optimum range to perform certain activities, such as topdressing,” Edwards said. “There is generally some leeway at either end of the dates given for producers to respond to their specific management needs and situations.”

As in all years, a producer needs to look at how many acres he or she has to topdress and the capacity to cover those acres.

“Producers who use a custom applicator may be at the mercy of the applicator’s availability, so they need to get on the applicator’s schedule as quickly as possible,” Edwards said. “Those who have the expertise and equipment to do their own topdressing have a bit more flexibility.”

Edwards said nitrogen fertilization remains an excellent return on investment, even at current prices, with producers who have N-rich strips in their fields likely having a better handle on how much nitrogen is needed than those working off field history.

Based on observations, N-rich strips are just starting to show in a few fields, said Brian Arnall, an OSU assistant professor whose Cooperative Extension, teaching and research efforts focus on precision nutrient management.

“Soil tests coming through the OSU laboratory show quite a bit of residual nitrogen is present in many fields,” he said. “It is likely that some fields will not need as much topdress nitrogen as is typically the case in a ‘normal’ year. Overall, though, topdressing is likely to pay off.”

Edwards said millers worldwide are increasingly selective when it comes to wheat quality.

“It is a buyer’s market and millers simply don’t have to accept wheat that does not meet their quality standards,” he said. “Anything that could negatively affect the protein content of the grain, leading to price discounts, is a matter of concern relative to Oklahoma’s reputation in the wheat flour marketplace.”

In a typical year, a producer who waits can make a more informed decision about crop nitrogen need than one who topdresses early, be more precise in managing nitrogen supplies and maximize the investment.

“The tricky part is waiting long enough to assess crop needs accurately without waiting too late,” Edwards said. “Nitrogen must be in the rooting zone by jointing. Taking time now to plan out a strategy can only strengthen an operation.”

In addition, long-range weather forecasts predict Oklahoma is in for a drier than normal winter.

“We could be in a situation where there are only a few opportunities to receive adequate rainfall to move nitrogen into the rooting zone,” Edwards said. “It will be important to have the nitrogen in place when this rainfall occurs.”